The aim of this study was to characterize and identify the mode of action of IC31？, a two-component vaccine adjuvant. We found that IC31？ was accumulated in human peripheral blood monocytes, MHC class II positive cells and monocyte-derived DCs (moDCs) but not in plasmacytoid DCs (pDCs). In the presence of IC31？ the differentiation of inflammatory CD1a+ moDCs and the secretion of chemokines, TNF-α and IL-6 cytokines was inhibited but the production of IFNβ was increased. Sustained addition of IC31？ to differentiating moDCs interfered with IκBα phosphorylation, while the level of phospho-IRF3 increased. We also showed that both IC31？ and its KLK component exhibited a booster effect on type I IFN responses induced by the specific ligands of TLR3 or TLR7/8, whereas TLR9 ligand induces type I IFN production only in the presence of IC31？ or ODN1. Furthermore, long term incubation of moDCs with IC31？ caused significantly higher expression of IRF and IFN genes than a single 24 hr treatment. The adjuvant activity of IC31？ on the IFN response was shown to be exerted through TLRs residing in the vesicular compartment of moDCs. Based on these results IC31？ was identified as a moDC modulatory adjuvant that sets the balance of the NF-κB and IRF3 mediated signaling pathways to the production of IFNβ. Thus IC31？ is emerging as a potent adjuvant to increase immune responses against intracellular pathogens and cancer in future vaccination strategies.
References
[1]
Coffman RL, Sher A, Seder RA (2010) Vaccine adjuvants: putting innate immunity to work. Immunity 33: 492–503.
[2]
Beauvillain C, Delneste Y, Scotet M, Peres A, Gascan H, et al. (2007) Neutrophils efficiently cross-prime naive T cells in vivo. Blood 110: 2965–2973.
[3]
Palucka K, Banchereau J, Mellman I (2010) Designing vaccines based on biology of human dendritic cell subsets. Immunity 33: 464–478.
[4]
Steinman RM, Hawiger D, Nussenzweig MC (2003) Tolerogenic dendritic cells. Annu Rev Immunol 21: 685–711.
[5]
Helft J, Ginhoux F, Bogunovic M, Merad M (2010) Origin and functional heterogeneity of non-lymphoid tissue dendritic cells in mice. Immunol Rev 234: 55–75.
[6]
Naik SH, Sathe P, Park HY, Metcalf D, Proietto AI, et al. (2007) Development of plasmacytoid and conventional dendritic cell subtypes from single precursor cells derived in vitro and in vivo. Nat Immunol 8: 1217–1226.
[7]
Shortman K, Naik SH (2007) Steady-state and inflammatory dendritic-cell development. Nat Rev Immunol 7: 19–30.
[8]
Geissmann F, Auffray C, Palframan R, Wirrig C, Ciocca A, et al. (2008) Blood monocytes: distinct subsets, how they relate to dendritic cells, and their possible roles in the regulation of T-cell responses. Immunol Cell Biol 86: 398–408.
[9]
Cheong C, Matos I, Choi JH, Dandamudi DB, Shrestha E, et al. (2010) Microbial stimulation fully differentiates monocytes to DC-SIGN/CD209(+) dendritic cells for immune T cell areas. Cell 143: 416–429.
[10]
Sallusto F, Lanzavecchia A (1994) Efficient presentation of soluble antigen by cultured human dendritic cells is maintained by granulocyte/macrophage colony-stimulating factor plus interleukin 4 and downregulated by tumor necrosis factor alpha. J Exp Med 179: 1109–1118.
[11]
Dustin ML, Depoil D (2011) New insights into the T cell synapse from single molecule techniques. Nat Rev Immunol 11: 672–684.
[12]
McLachlan JB, Shelburne CP, Hart JP, Pizzo SV, Goyal R, et al. (2008) Mast cell activators: a new class of highly effective vaccine adjuvants. Nat Med 14: 536–541.
[13]
De Gregorio E, D'Oro U, Wack A (2009) Immunology of TLR-independent vaccine adjuvants. Curr Opin Immunol 21: 339–345.
[14]
Trinchieri G, Sher A (2007) Cooperation of Toll-like receptor signals in innate immune defence. Nat Rev Immunol 7: 179–190.
[15]
Wack A, Baudner BC, Hilbert AK, Manini I, Nuti S, et al. (2008) Combination adjuvants for the induction of potent, long-lasting antibody and T-cell responses to influenza vaccine in mice. Vaccine 26: 552–561.
[16]
Kool M, Soullie T, van Nimwegen M, Willart MA, Muskens F, et al. (2008) Alum adjuvant boosts adaptive immunity by inducing uric acid and activating inflammatory dendritic cells. J Exp Med 205: 869–882.
[17]
Fritz JH, Brunner S, Birnstiel ML, Buschle M, Gabain A, et al. (2004) The artificial antimicrobial peptide KLKLLLLLKLK induces predominantly a TH2-type immune response to co-injected antigens. Vaccine 22: 3274–3284.
[18]
Kritsch CE, Berger A, Heinrich-Cseh C, Bugajska-Schretter A, Zauner W (2005) Separation and quantification of a novel two-component vaccine adjuvant. J Chromatogr B Analyt Technol Biomed Life Sci 822: 263–270.
[19]
Schellack C, Prinz K, Egyed A, Fritz JH, Wittmann B, et al. (2006) IC31, a novel adjuvant signaling via TLR9, induces potent cellular and humoral immune responses. Vaccine 24: 5461–5472.
[20]
Agger EM, Rosenkrands I, Olsen AW, Hatch G, Williams A, et al. (2006) Protective immunity to tuberculosis with Ag85B-ESAT-6 in a synthetic cationic adjuvant system IC31. Vaccine 24: 5452–5460.
[21]
Kamath AT, Valenti MP, Rochat AF, Agger EM, Lingnau K, et al. (2008) Protective anti-mycobacterial T cell responses through exquisite in vivo activation of vaccine-targeted dendritic cells. Eur J Immunol 38: 1247–1256.
[22]
Kamath AT, Rochat AF, Valenti MP, Agger EM, Lingnau K, et al. (2008) Adult-like anti-mycobacterial T cell and in vivo dendritic cell responses following neonatal immunization with Ag85B-ESAT-6 in the IC31 adjuvant. PLoS One 3: e3683.
[23]
van Dissel JT, Arend SM, Prins C, Bang P, Tingskov PN, et al. (2010) Ag85B-ESAT-6 adjuvanted with IC31 promotes strong and long-lived Mycobacterium tuberculosis specific T cell responses in naive human volunteers. Vaccine 28: 3571–3581.
[24]
van Dissel JT, Soonawala D, Joosten SA, Prins C, Arend SM, et al. (2011) Ag85B-ESAT-6 adjuvanted with IC31(R) promotes strong and long-lived Mycobacterium tuberculosis specific T cell responses in volunteers with previous BCG vaccination or tuberculosis infection. Vaccine 29: 2100–2109.
[25]
Aichinger MC, Ortbauer M, Reipert S, Zauner W, Bogner P, et al. (2008) Unique membrane-interacting properties of the immunostimulatory cationic peptide KLKL(5)KLK (KLK). Cell Biol Int 32: 1449–1458.
[26]
Aichinger MC, Ginzler M, Weghuber J, Zimmermann L, Riedl K, et al. (2011) Adjuvating the adjuvant: facilitated delivery of an immunomodulatory oligonucleotide to TLR9 by a cationic antimicrobial peptide in dendritic cells. Vaccine 29: 426–436.
[27]
Lingnau K, Riedl K, von Gabain A (2007) IC31 and IC30, novel types of vaccine adjuvant based on peptide delivery systems. Expert Rev Vaccines 6: 741–746.
[28]
Pilz A, Kratky W, Stockinger S, Simma O, Kalinke U, et al. (2009) Dendritic cells require STAT-1 phosphorylated at its transactivating domain for the induction of peptide-specific CTL. J Immunol 183: 2286–2293.
[29]
Prchal M, Pilz A, Simma O, Lingnau K, von Gabain A, et al. (2009) Type I interferons as mediators of immune adjuvants for T- and B cell-dependent acquired immunity. Vaccine 27 Suppl 6G17–20.
[30]
Kaisho T (2010) Molecular mechanisms for plasmacytoid dendritic cell function and development. Vaccine 28: 8046–8047.
[31]
Benko S, Magyarics Z, Szabo A, Rajnavolgyi E (2008) Dendritic cell subtypes as primary targets of vaccines: the emerging role and cross-talk of pattern recognition receptors. Biol Chem 389: 469–485.
[32]
Magyarics Z, Csillag A, Pazmandi K, Rajnavolgyi E, Bacsi A (2008) Identification of plasmacytoid pre-dendritic cells by one-color flow cytometry for phenotype screening. Cytometry A 73: 254–258.
[33]
Gogolak P, Rethi B, Szatmari I, Lanyi A, Dezso B, et al. (2007) Differentiation of CD1a- and CD1a+ monocyte-derived dendritic cells is biased by lipid environment and PPARgamma. Blood 109: 643–652.
[34]
Palm NW, Medzhitov R (2009) Pattern recognition receptors and control of adaptive immunity. Immunol Rev 227: 221–233.
[35]
Selvarajoo K, Takada Y, Gohda J, Helmy M, Akira S, et al. (2008) Signaling flux redistribution at toll-like receptor pathway junctions. PLoS One 3: e3430.
[36]
Honda K, Taniguchi A (2006) IRFs: master regulators of signalling by Toll-like receptors and cytosolic pattern-recognition receptors. Nat Rev Immunol 6: 644–658.
[37]
Szabo A, Bene K, Gogolák P, Réthi B, Lányi A, et al. (2012) RLR-mediated production of interferon-β by a human dendritic cell subset and its role in virus-specific immunity. J Leukoc Biol 92: 159–169.
[38]
Berghofer B, Haley G, Frommer T, Bein G, Hackstein H (2007) Natural and synthetic TLR7 ligands inhibit CpG-A- and CpG-C-oligodeoxynucleotide-induced IFN-alpha production. J Immunol 178: 4072–4079.
[39]
Butchi NB, Du M, Peterson KE (2010) Interactions between TLR7 and TLR9 agonists and receptors regulate innate immune responses by astrocytes and microglia. Glia 58: 650–664.
[40]
Pulendran B, Tang H, Manicassamy S (2010) Programming dendritic cells to induce T(H)2 and tolerogenic responses. Nat Immunol 11: 647–655.
[41]
Blander JM, Medzhitov R (2006) Toll-dependent selection of microbial antigens for presentation by dendritic cells. Nature 440: 808–812.
[42]
Joffre O, Nolte MA, Sporri R, Reis e Sousa C (2009) Inflammatory signals in dendritic cell activation and the induction of adaptive immunity. Immunol Rev 227: 234–247.
[43]
Gonzalez-Navajas JM, Lee J, David M, Raz E (2012) Immunomodulatory functions of type I interferons. Nat Rev Immunol 12: 125–135.
[44]
Xiao HB, Zhou WY, Chen XF, Mei J, Lv ZW, et al.. (2011) Interferon-beta efficiently inhibited endothelial progenitor cell-induced tumor angiogenesis. Gene Ther. Epub ahead of print. doi:10.1038/gt.2011.171.
